Closes obsproject/obs-studio#3005

If an image source isn't visible there is no point polling for changes
during the time it's hidden as no one will see them. Should the image
be on unreachable media such as an unavailable network share, this
check would cause the graphics thread to periodically stall trying to
detect changes of a non-visible image source.

If the image is modified while it's hidden, the updated file will now
be loaded as soon as the source is made visible - the update timer
intentionally ticks up while hidden.

Partially fixes some of the behavior described in
https://github.com/obsproject/obs-studio/issues/3007, a full fix
likely requires significant changes to support OS-specific file change
notification APIs.

This reverts commit 636f0bfd, reversing
changes made to b9ea45e4.

Use general layout and 0 access masks for external synchronization as
specified in the spec.

Also set pipeline stages for maximum synchronization just in case
because it doesn't seem like the pipeline stages are specified.

"Vulkan-incompatible APIs will require the image to be in the GENERAL
layout whenever they are accessing them."

"Whilst it is not invalid to provide destination or source access masks
for memory barriers used for release or acquire operations,
respectively, they have no practical effect. Access after a release
operation has undefined results, and so visibility for those accesses
has no practical effect. Similarly, write access before an acquire
operation will produce undefined results for future access, so
availability of those writes has no practical use. In an earlier version
of the specification, these were required to match on both sides - but
this was subsequently relaxed. These masks should be set to 0."

Combine MMBRC and CQM parameters into a subjective video
enhancement box

All strings were treated as partial matches before, which caused a
false positive with any executable beginning with "time", notably
affecting the game "Timelie" which used Timelie.exe.

As of 3.17 using find_package_handle_standard_args checks that the name
of the FindXXX file and the first argument are the same case.

Some modules used non-standard variables or the old singular variables
instead of plurals. This normalizes variable usage to the new-style.

Some CMakeLists.txt did custom error checking instead of propagating
find_package errors. These were changes to call find_package with
REQUIRED or without QUIET where needed and shortens the custom status
messages. This helps users who want to enable that functionality see
what precisely wasnt found.

This reverts commit d777000a, reversing
changes made to c9e5f30a.

This replaces the ffmpeg-encoded-output which had serious issues
(missing headers, muxing issues with non compliant mpegts streams) with
an output grafted from obs-ffmpeg-mux.

Moves the code that generates a file read error message to its own
function for the sake of cleaning things up a bit.

Fixes issue where there are two window handles for minimized Calculator,
and OBS picks the wrong one.

Enable AVC VDEnc (fixed function encode) on ICL+

Simplify UI options by combining LookAhead Depth and Async Depth into
latency mode option. Ultra-low, low, and normal will set these two
encode parameters accordingly.

WGC will give up on a window that it fails to capture, but that
shouldn't stop it from attempting to capture new windows.

Fixes #2928.

Don't allow unsupported Vulkan formats to fall back to B8G8R8A8.
Probably better to fail completely than do an illegal copy.

Also remove bad conversion for VK_FORMAT_A2R10G10B10_UNORM_PACK32.
Red and blue channels were reversed, and there's no DXGI equivalent.

Addresses #2796. We can do more later if justified.

Better practice for the tracked size to be nonzero.

This does NOT speed up window capture significantly.

Make WGC window capture recover from GraphicsCaptureItem closure, which
can occur when following links in fullscreen Chrome for example.

Fix an issue in the way AVFrames were handled in the FFmpeg
encoder plugin, which could lead to tearing in the encoded
video due to data races in the AVFrame and AVBuffer.

This is fixed by calling av_frame_make_writable which ensures
the frame and its associated buffer are writable. If its not,
it will copy the AVFrame, create a new AVBuffer for it and
decrease the refcount of the old AVFrame and AVBuffer.
This way OBS always ends up with a usable buffer to write into
which is not still used by the encoder while avoiding a copy
when unnecessary.

Closes obsproject/obs-studio#2813

This implements OSS audio input capturing support for OSS-capable OSes.
FreeBSD and DragonFly (not yet tested on) supports are added as a
starting point.

The error message in the process_packet function was prefixed with
"receive_audio" because it was previously from code in the encode_audio
function which was called from the receive_audio function. This is just
a string change to avoid being misled to believe that the error is
always audio related.

If we fallback to ffmpeg NVENC, the error from new NVENC might still be
present in the encoder structure. Given that this provides a lot more
actionable information to the user, let's use it if possible.

While discussing the Flatpak RFC [1], it was spotted that the
LUT filter couldn't open the file selection dialog. It was
explained, then, that the proper formats were either composed
of "User Label (file extensions)", or "file extensions", and
the LUT filter was setting "(file extensions)" without the
actual user label.

While this works on a standard Qt file selection dialog, it
cannot be properly formatted as a set of D-Bus filters, thus
breaking the sandbox integration.

Add a simple user label to the LUT file filter.

[1] https://github.com/obsproject/rfcs/pull/21#issuecomment-619106757